Listing is for a brand new never used CLASS 4, office chair seat height adjustment pneumatic gas lift cylinder. 4.5 stroke (seat travel from lowest to highest settings). Exceeds ANSI/BIFMA5.1-2011 standards, based on the specs of this cylinder, it’s load capacity is 350 pounds. Length Compressed: 11.5″ Fully Extended: 16″ Travel: 4.5″, Cylinder Diameter: 28mm (1.1″) Column Diameter: 50mm (approx 2). After install, If the chair can’t lift normally. Two screws located near where the cable attaches need to be adjusted, see photo 5. Also can fit the remastered Aeron chair. Package Include: 1 x gas cylinderchair not included. Samhongsa was founded in 1971, is a professional production and sales of Cylinder for office chair. Samhongsa have advanced production equipment and testing equipment and improved management system. Samhongsa always insist on the operation idea of “human-oriented, honesty first, lean management and excellence” Providing perfect quality and service for users and possess the good reputation. Samhongsa’s cylinder have acquired and through eight world standards certificationsSuch as: BIFMA;LGA;TUV;SGS, ect. Samhongsa have built a friendly, long-term with Herman Miller, Allsteel, Steelcase, HON, etc.